Stereotactic guide for use in the creation of destructive brain lesions



STEREOTACTIC GUIDE FbR USE IN THE CREATION Aug. 12, 1969 0 c ZEIZIS3,460,537

OF DESTRUCTIVEZ BRAIN LESIONS Filed Sept. 26. 1966 2 Sheets-$heet lINVENTOR DONALD C.ZE|S

Aug. 12, 1969 ms 3,460,537

STEREOTAGTIG GU FOR USE IN THE CREATION TRUCTIVE BRAIN LESIONS FiledSept. 26. 1966 OF DES 2 Sheets-Sheet 2 "1R "WWII/IA 2o l7 2 24 I 35 I52o g ill!!!" United States Patent 3,460,537 STEREOTACTIC GUIDE FOR USEIN THE CREA- TION 0F DESTRUCTIVE BRAIN LESIONS Donald C. Zeis, 2122Roselawn St., Sarasota, Fla. 33581 Filed Sept. 26, 1966, Ser. No.581,793 Int. Cl. A61b 17/32; A61n 3/00 US. Cl. 128-303 3 Claims ABSTRACTOF THE DISCLOSURE This invention relates to a stereotactic guide forholding and adjusting a cannula with maximum accuracy and a positivefinite degree, for use by surgeons in the cryosurgical treatment ofParkinsons disease, deep seated brain tumors, hyperkinetic disorders andother maladies of the human brain, in which an accurately placeddestructive cryosurgical lesion is desired in the form of treatment.

The present invention comprises a cannula holder and guide for thepurpose specified, which is small, compact,

is easy to sterilize and store when not in use, one which is a singlecompact structure embodying no parts which must be removed for storageor added when applying it to a patient.

The stereotactic guide for cannulas is so designed and constructed thatit may be attached directly to the skull of a patient without anyaccessory devices and embodies means to rigidly hold the guide in placeon the patients skull, whereby movement of the patients head or bodywill not affect the positioning of the cannula.

Further the stereotatic guide embodies means whereby when the cannula isin position in and anchored to the guide, the cannula may be moved inconjunction with its holding element in controlled micromatic movementin a substantially longitudinal plane through an arc of three hundredand sixty degrees (360) to provide substantially infinite positioning ofthe brain treating end of the cannula within such range and alsoprovides means for firmly locking the cannula in such position, whilepermitting limited longitudinal movement of the cannula.

In the drawings:

FIGURE 1 is a top plan view of the stereotactic guide.

FIGURE 2 is a side elevation of the stereotactic guide.

FIGURE 3 is a bottom plan view of the guide.

FIGURE 4 is a side elevation of the stereotactic guide taken at rightangles to the view shown in FIGURE 2 and showing a cannula in place inthe guide.

FIGURE 5 is a fragmentary vertical section through the guide taken onthe line 5-5 of FIGURE 1.

FIGURE 6 is a detail vertical section through the attaching element ofthe ring and taken on the line 6-6 of FIGURE 1. a

"Ice

FIGURE 7 is a fragmentary longitudinal section taken on line 7-7 ofFIGURE 4.

FIGURE 8 is a cross section taken on line 83 of FIG- URE 4.

In cryosurgical treatment of Parkinsons disease, deep seated braintumors, hyperkinetic disorders and other maladies of the human brain theseat or source of the ailment in the brain is destroyed or treated by acryosurgical lesion created by the use of a cannula inserted into thebrain to the exact point of the seat or source of the malady and it isnecessary that no other part of the brain be affected by the lesion,therefore extreme accuracy and positive minimum of movement of thecannula is necessary. With the apparatus in use today by surgeonsperforming such operations any movement of the head of the patient mayprove fatal to him, and consequently expensive complicated apparatus isrequired, which is also very diflicult to sterilize.

The stereotactic guide for cannulas is so designed and is rigidlyattached to the skull of the patient and is moveaole as a whole with anymovement of the head of the patient, thereby eliminating liability of adamaging accident due to movement of the patients head or body.

To permit rigid attachment of the guide to a patients head the guideembodies an attaching element 1 which includes the main body 2 having atapered ring 3 depending therefrom. An inserting ring or collar 4 isformed on the outer end of the tapered ring'3. The inserting ring 4 isof a width equal to the thickness of a human skull. The ring or collar 4is inserted in a skull trephination of such size and shape that theouter surface or wall of the collar 4 will fit fairly snugly therein,and the collar 4 terminates, at its junction with the ring 3, in ashoulder 5 which forms a stop for limiting the insertion of the ring 4into the patients skull.

Anchoring means are provided for firmly anchoring the attaching elementto the patients skull in such manner as to prohibit possible independentmovement of the skull and attaching element, and since the entirestereotactic guide is rigidly carried by the attaching element (ashereinafter described) any movement, as a Whole, of the guide relativeto the head of the patient will be prevented and vice versa.

One such anchoring means is shown in FIGURE 6 of the drawings, and whilethe structure shown has been found satisfactory in actual use, it is tobe understood that this invention is not to be limited to the sp cificanchoring means shown and hereafter described except only as limited bythe claims hereof.

The attaching element 1 has a plurality of openings 7 therein, locatedat circumferentially spaced points about its vertical axis whichopenings 7 open out through the ring 3 and collar 4 at their outersides. Skull gripping pins 8 are inserted in the openings 7 and extendup into the enlarged portions 9 of the openings 7, wherein the upperdiameter-reduced portions 10 of the pins 8 are engaged by the adjustingscrews 11. The adjusting screws 11 are threaded in the attaching element1 and threaded movement of the screws 11 move the pins 8 on fulcrums atthe point of contact of the pins 8 with the walls of the openings 7 atthe upper terminus of the portions of the openings 7 which open outthrough the outer walls of the tapered rings 3. The pins 8 extendupwardly into the openings at a slight angle to the vertical while theadjusting screws are inclined at a slight angle to the horizontal, thuswhen the adjusting screws are threaded inwardly the lower ends of thepins 8 will be moved outwardly for engagement, through the openings inthe inserting ring or collar 4 with the wall of the opening in the skullof the patient. The surfaces of the pins 8 which engage the wall of theskull opening are roughened as by threading, knurling or in any othersuitable manner to firmly grip the walls of the skull opening andprevent any movement whatever of the attaching element relative to thepatients head.

The body 2 of the attaching element 1 has an axial bore 12 intermediatethe ends of which is formed a seat 14, the walls of which are curved toform a seat for the ball 15 which is formed on the lower end of thecannula guiding and holding tube 16. The bore 12 tapers outwardly as itextends upwardly from and downwardly from the seat 14 as clearly shownin FIGURE 6 of the drawings.

The tube 16 slidably passes through a ball 16' which engages in a seat17' formed in the collar 17. A spring 35 is mounted upon the tube 16 andits ends engage the balls 15 and 16' to spring load these balls andmaintain them in their seats, thereby eliminating any misalignment. Thisstructure will also compensate for the slight variation in the radialarc links generated in the movement of the tube 16 during positioning ofa cannula as will be hereinafter described. This manner of mounting ofthe tube 16 will also eliminate any play in its movement, which mightaffect adversely the positioning of a cannula.

The trunnions 18 and 19 are slidably supported by brackets 20 which arepivotally attached to the attach ing element 1 such as by screws 21", orin any other suitable manner.

The trunnion 19 is threaded and has a thumb nut 21 threaded upon itsouter end. The hub 22 of the nut 21 engages the bracket 20 so that whenthe nut 21 is rotated the trunnion will be moved longitudinally ineither direction depending upon the direction of rotation of the nut 21.At the time of longitudinal movement of the trunnion 19 the trunnion 18will also move longitudinally, sliding in its bearing in the bracket 20,and thus the tube 16 will be moved on, its pivot point formed by theball 15 in the socket 14, in paths such as indicated by the dot and dashlines A and B in FIGURE of the drawings. A shoulder 23 is formed uponthe trunnion 18 and provides a stop for the pivotal movement of the tube16 in its direction indicated by arrow C by its contact with the bracket20.

The hub 21' of the nut 21 extends through the bracket 20 and its innerend forms a stop for limiting the pivotal or swinging movement in thedirection indicated by the arrow A. These stops are necessary as toprevent a cannula carried by the tube 16 (see FIGURE 4 of the drawings)from engaging the walls of the tapered opening 12, because the cannulais a very delicate instrument and such contact might injure it.

A collar 24 is mounted on the hub 21' adjacent to the bracket 20 and ithas a threaded stem 25 attached thereto and extending substantially atright angles to the trunnion 19. The outer end of the threaded stem 25is supported by a bracket 26 attached to and extending upwardly from theattaching element 1. A nut 27 is mounted on the stem 25 and engages thebracket 26 so that when the nut 27 is rotated the trunnions 18 and 19will move longitudinally and consequently the tube 16 will be moved uponthe pivots provided by the screws 21' in a path at right angles to thepath of movement provided by rotation of the nut 21. Any suitable stops(not shown) may be provided to limit the movement of the tube 16 by thestem 25 and nut 27. Thus by rotation of the nuts 21 and 27 a cannulaindicated at 30 in FIGURE 4 of the drawings may be moved in smallincrements provided by alternate rotation of the nuts 21 and 27 intoinfinite positions within the 360 degree radius permitted by the balland socket 14 and confined by the walls of the tapered opening 12 in theattaching element 1.

The cannula which forms no part of this invention has a stop collar 31mounted thereon which carries a locking screw 31', so that a surgeon maytighten the stop collar at the desired position on the cannula to insurethe proper length of the portion of the cannula which projects beyondthe collar 4.

A steadying or bracing rod 37 is carried by the brackets 20 and engagesthe collar 17 as clearly shown in FIG- URE 1 of the drawings, to preventrotation or rocking of the collar 17 and the trunnions 18 and 19 whilethe nut 21 or 27 is being rotated or adjusted.

Cannula are made in different diameters, and to compensate for slightvariances in the dameter of one cannula from another, the upper end ofthe sleeve 16 is split as shown at 50 in FIGURE 5 for a short distanceinwardly from its end and a clamping collar 38 is mounted thereon bymeans of which the split end of the sleeve 16 may be pinched into tightclamping engagement with a cannula.

For the purpose of permitting use of cannulas of small diameter, asleeve 40 is provided which slides into the sleeve 16 when needed andwhich is tightly clamped in the sleeve 16 by the clamping nut 38. Thesleeve 40 is also split for a short distance inwardly from its receivingend and has a clamping nut 44 thereon to clamp a cannula tightly inposition in the sleeve 40.

The threads on the trunnion 19, stem 25, and nuts 21 and 27 providemicrometer adjustment of the angles of the position of the sleeve 16 andby knowledge of this and the degree of movement provided by each turn orpartial turn of the nuts 21 and 27, a surgeon may in conjunction withX-ray place the cannula in the exact spot to treat the affected part ofa human brain, without liability of slippage or mispositioning of thecannula.

While various specific structures to provide the desired degrees ofadjustment, locking of elements in position, etc. are shown anddescribed herein, it is to be understood that the invention is notlimited to the structure shown and described, but may be varied aspractice may dictate without departing from the invention, so long assuch structures are embraced in the claims hereto appended.

What is claimed is:

1. In a stereotacetic guide for use in cryosurgical treatment of abrain, an attaching element for direct attachment to the skull of apatient, a cannula carrying guide carried by said attaching element andmeans supported from said attaching element to provide substantiallyinfinite adjusted positioning of a cannula carried by the guide, acollar formed on said attaching element for fitting in an opening in askull, and means on said collar to limit the degree of insertion of thecollar into the opening in the skull, means carried by the attachingelement for projection beyond the circumference of said collar to gripthe walls of a skull opening, and means for moving said gripping meansinto and out of gripping position.

2. In a stereotactic guide, as claimed in claim 1, wherein saidattaching element has an axial bore extending therethrough with anintermediate portion shaped to form a concave curved seat, a ball formedon the lower end of said cannula guide and seated in the seat formed inthe attaching element, the portion of the bore extending outwardly fromsaid seat being tapered to form substantially a conical space openingout through the lower end of the attaching element.

3. In a stereotactic guide for use in cryosurgical treatment of a brain,an attaching element for direct attachment to the skull of a patient, acannula carrying guide carried by said attaching element and meanssupported from said attaching element to provide substantially infiniteadjusted positioning of a cannula carried by the guide, said attachingelement has an axial bore extending therethrough with an intermediateportion shaped to form a concave curved seat, a ball formed of the lowerend of said cannula guide and seated in the seat formed in the attachingelement, the portion of the bore extending outwardly from said seatbeing tapered to form substantially a conical space opening out throughthe lower end of the attachment element the outer surface of saidattaching element being smooth for sliding into the opening in a skull,and means carried by said attaching element for projection beyond itsouter smooth surface for gripping the wall of the skull at separatedpoints about the wall of the opening, and means for moving said skullwalled gripping means into and out of gripping position.

References Cited UNITED STATES PATENTS L. W. TRAPP, Primary Examiner

